title: Thermodynamic investigation of coordination-networked systems of [Mn4] single-molecule magnets under pressure.
abstract: Low temperature heat capacity measurements under pressure were performed for tiny single crystals of two-dimensional coordination-networked compounds consisting of [Mn(4)] single-molecule magnets (SMMs) by the ac temperature modulation technique. Systematic variations of the peak temperature and the peak width of the thermal anomalies produced by pressure were clearly detected using two ruthenium oxide resistance chips in the Cu-Be clamp-type cell. A linear increase of the Néel temperature for an ordering set of large SMM spins with S=9 was observed in [Mn(4)(hmp)(6){N(CN)(2)}(2)](ClO(4))(2), while a non-monotonic variation of the peak temperatures and peak shapes was observed in [Mn(4)(hmp)(4)Br(2)(OMe)(2){N(CN)(2)}(2)](ClO(4))(2)·2THF·0.5H(2)O (hmp(-)=2-hydroxymethylpyridinate; N(CN)(2)(-)=dicyanamide as the linker among SMMs). We also report on thermodynamic behavior produced by changing external pressures and magnetic fields. The results are discussed in terms of the tilting angle of Ising axes in the two-dimensional plane.
authors.affiliation: Department of Chemistry, Graduate School of Science, Osaka University, Machikaneyama, Toyonaka, Osaka 560-0043, Japan.
authors.forename: O
authors.initials: O
authors.lastname: Kubota
authors.forename: S
authors.initials: S
authors.lastname: Fukuoka
authors.forename: Y
authors.initials: Y
authors.lastname: Nakazawa
authors.forename: K
authors.initials: K
authors.lastname: Nakata
authors.forename: M
authors.initials: M
authors.lastname: Yamashita
authors.forename: H
authors.initials: H
authors.lastname: Miyasaka